Madison Keys upsets Li Na for biggest win of her career

Madison Keys is currently No. 62 in the WTA World Rankings, and wasn't sure she would get a chance to play in the Madrid Open after losing to Bethanie Mattek-Sands in the final round of qualifying. (Julian Finney/Getty Images)

What was Madison Keys doing when she found out that she had 10 minutes before she would be facing 2011 French Open champion Li Na on center court? Sitting on a couch in the player lounge doing her algebra homework.

About an hour and a half later, the 18-year old had notched the biggest win of her young career, beating the fifth-ranked Li 6-3, 6-2 in the first round of the Mutua Madrid Open. The win was Keys' first over a Top 10 player as well as her first over a Slam champion.

"I had practice really early this morning because I didn't think I was in [the tournament]," said Keys, who lost in the final round of qualifying to Bethanie Mattek-Sands on Saturday. Despite the loss, she still had a chance to slip into the main draw as a "lucky loser" if another player withdrew from the tournament. A few minutes before Li's match was set to begin, she got word that Li's scheduled opponent Tamira Paszek had withdrawn due to an upper respiratory illness. Keys packed up her books and scrambled to get on court.

"I just kind of sat around waiting all day and, like, 10 minutes before the match I got a text message, 'Yeah, no, you're going on so go get ready!' And then we went on 10 minutes later," she said with a giggle.

The win over Li was a revenge match of sorts. The two faced off earlier this year in Keys' first WTA quarterfinal match in Sydney. Though Keys had her chances to cause the upset then, Li came back from a set down to win 4-6, 7-6 (2), 6-2. After the match, the Chinese national was glowing with praise for the teen, noting her belief that she was a a Top 15 player in the making.

This time around, Keys says having short notice of the match helped her stay focused. "Not over-thinking it all day and sitting around and kind of worrying about it I think really helped. All of a sudden I was so excited and adrenaline was going and all that. I just kind of started playing and felt really good and I was able to win. And it was my first red clay court tournament since I was, like, 14. So getting a big win feels good."

Li, who made the final in Stuttgart a week ago, struggled to find her range early and littered the stat sheet with unforced errors. She hit a whopping 34 unforced errors to just eight winners, while Keys was much cleaner, hitting 11 unforced to seven winners. It wasn't a pretty match but it was a huge confidence booster for Keys, who became the first woman outside of the Top 4 to beat Li this year.